The food warming unit of the present invention is predicated on a similar heating principle and concept as the ovens described in U.S. Pat. No. 3,521,030 issued Jul. 21, 1970 and U.S. Pat. No. 3,800,123 issued on Mar. 26, 1974. Both of these patents were developed and owned by the predecessor to the assignee of the present invention. The oven described in the above-mentioned patents includes one or more electric heating cables encased in the walls of the oven, and which extend around the interior compartment. The ovens described in the patents include an appropriate electric circuit for energizing the electric heating cable to cause it to generate heat in the oven.
Food warming or holding cabinets are well known appliances used to maintain heated food at a desired serving temperature. These warming cabinets have become valuable tools in the food industry, particularly in fast food and institutional applications. They allow food to be cooked in advance and then held at a desired temperature. The cabinets must be large enough to hold many servings, yet maintain a uniform temperature throughout. The food texture, moisture and flavor must be maintained during the time the food is held in the cabinet. The most important quality to be maintained is food moisture.
Many attempts have been made in the prior art to provide food warming devices having humidity and temperature control. The great majority of these devices are complex systems which require a separate well or bath for heating water with separate controls and heaters. Such designs require increased water usage and are more expensive to build and maintain. In some cases, circulating air within the warming and holding device contributes to the drying out of the food stored within.
Accordingly, it remains desirable to provide a food warming cabinet which retards evaporation of moisture from the food in the cabinet. It is also desirable to provide a food warming cabinet which is more economical to produce than competitive designs utilizing dedicated, hot water bath designs. It is likewise desirable to provide a food warming cabinet which measures temperature and door openings, and automatically adjusts to replenish the lost moisture in order to maintain the quality of the cooked food held within.